Introduces the Birlings, establishes their social positions and gives some clues to the audience that this depiction of a happy family is not quite what it seems
May indicate the characters will be made to repeat the events of the evening, with another opportunity of redemption for those characters who had refused to do so
Priestley deliberately uses dramatic irony, in part, to portray Arthur Birling as foolish when the character smugly boasts about the Titanic ship and the future prospects of peace and prosperity